1. Field of the Invention
This invention relates to a printer, printer control method, program therefor, and recording medium storing the program, for example, based on the scheme of a printer configured to receive data from a computer through a single logic channel.
2. Description of the Related Background Art
Printers, in general, are configured to be supplied with print data to be printed and control data for controlling the printer. The print data and the control data supplied are stored in a receiving buffer of the printer.
In this case, if a computer and a printer are connected by an interface specification having only one logic channel, the print data and the control data are transmitted from the computer to the printer through the single logic channel, and they are stored in the receiving buffer in the order of arrival.
Typical control commands contained in such control data include a cancel command for canceling the print of print data heretofore transmitted, a status reply command requesting an answer about settings of the printer, and a paper size instruction command designating the paper size for the print data to be next printed.
The print data and the control data stored in the receiving buffer are sequentially read out, language-interpreted, and developed into bit image data in case of the print data, or processed in accordance with the control command in case of the control data.
Such a printer with an interface specification having a single logic channel could process data only in the order of transmission from the computer, and involved various inconveniences.
For example, when a cancel command is transmitted from the computer to the printer to cancel the print of the print data already transmitted from the computer to the printer, the printer could interpret that cancel command only after finishing interpretation of the preceding print command instructing the print of that print data. As a result, the printer often executes the needless print.